// Science · Glossary

Cysteine Sulfur Pathway

⚗️ Science First mentioned: Ep. 228

The biochemical pathway through which the amino acid cysteine donates sulfur to form volatile sulfur compounds in cannabis. Cysteine's sulfhydryl group undergoes prenylation to produce thiols, thiolates, and other aromatic sulfur compounds that define the 'gas' and 'skunk' aromas.

Ian from Abstrax detailed on the aromatic volatile episode how sulfur is a highly sought-after element in biochemistry and that cysteine versus methionine as precursors preferentially produce different end products — thiolates versus thiols. The pathway involves transfer of sulfur from cysteine through prenylation reactions, with the resulting compounds interacting with terpenes and other aromatics to create the complex dankness profile. Nutrient experiments were referenced showing how sulfur inputs affect aromatic outcomes.

Ep. 228 Aromatic Volatiles Deep Dive